"The average American spends 20 hours a week on it – listening to music. Historically, about 3 of that is spent on music that you own; so, on-demand let's call it. And about 17 of it is spent listening to radio," he says.

Westergren thinks Spotify falls into the 3 hour on-demand category while Pandora helps make up the 17 hours of radio listening.

Watch the founder and Chief Strategy Officer of Pandora talk about the future of his company and how music consumption will change.